Mudflats, or intertidal zones, are challenging habitats: they are flats that run dry at low tide and the water depth is constantly changing. As a result, temperature, salinity and oxygen levels vary widely. Climate change is magnifying these fluctuations. Temperatures are rising and heatwaves are more frequent in all scenarios envisaged by the Royal Netherlands Meteorological Institute (KNMI). A species such as the cockle, an important food source for birds, may face difficulties: reduced growth, reduced reproduction or even mortality.

In recent years, nitrous oxide (N₂O) has become a major concern in wastewater treatment. N₂O is a by-product of biological wastewater treatment. Since it is a greenhouse gas around 300 times more potent than CO₂, the sector is exploring ways of quantifying and reducing N₂O emissions both within and outside the Netherlands. In partnership with AM-Team, Evides Industriewater combined modelling with temporary on-site monitoring to accelerate the path to net-zero emissions.

The year 2019 saw the publication of the Climate Scan: an analysis of the effects of climate change on the ecology of our large bodies of water. Given that both climate trends and knowledge development have progressed since, an update of the Climate Scan is in the pipeline. What will it say about the effect of rising water temperature on oxygen availability and attenuation of temperature fluctuations in water?

At the coast, PFAS – also known as 'forever chemicals' – are carried ashore in significant amounts via sea spray. Small droplets of seawater are released into the air by breaking waves, thereby reaching the coast. In the Netherlands, pre-treated river water is infiltrated into coastal dunes as a purification step in the production of drinking water. The fate of PFAS during this process is not yet fully understood.

Water companies put a lot of effort in reducing phosphorus emissions from wastewater treatment plants particularly if this effluent is discharged into phosphorus-sensitive waters. A potential measure is post treating the effluent with iron oxide granules. But how should this be approached? And does it also work on a practical scale, or only in the lab? BiOPhree® has been shown to reduce phosphorus (P) levels in WWTP effluent from 1 mg/l to less than 0.1 mg/l. It has also proven able to do so effectively and cost-efficiently in practice.

Aquafarm is a nature-based and low-tech method for the processing of sludge and secondary treatment of effluent. Wageningen Environmental Research and Radboud University have carried out scientific research into whether and how the natural processes involved in this method can contribute to the future of water treatment.

PCR allows easy and rapid detection of bacterial DNA. However, it does not determine whether the bacteria detected are alive or dead. Pre-culture PCR is a technique from food diagnostics for the rapid screening of live pathogenic bacteria. Vitens Water Expertise Centre is exploring whether this method is suitable for screening water, including drinking water, for pathogens such as E. coli.

Shoreline erosion is often combatted through harsh interventions. This approach is usually successful at preventing further erosion, but can also disrupt naturally occurring processes and ecosystems and offers little flexibility.

Based on interviews with hands-on experts, a study has explored what lessons can be learned from practice in terms of operation, sustainability, management, maintenance and the tendering process for powdered activated carbon systems at WWTPs.

When it comes to achieving good water conditions, chemical and ecological quality both play an important role. The presence and variation of riparian and aquatic plants help determine the ecological quality of the water. However, biodiversity in and around water often leaves much to be desired, particularly in agricultural areas. Some farmers are therefore working to improve ecological water quality by taking a more natural approach to landscaping ditches and through ecological management. What impact do these management and landscaping measures have on the ecological quality of ditches in agricultural areas?